By Maurizio Bertoli of MB Stone Restoration & Supply, Inc.
Marble and Granite Installations in Residential Dwellings Daily Maintenance – DOs ‘n’ DON’Ts Congratulations, you’ve got one of Mother Nature best in your home!
It is time now to make sure that you’re going to follow a few basic guidelines for its proper maintenance and preservation. Maintenance of natural stone is not much more difficult than any other material you’re familiar with. The difference is mostly in the cleaning agents. Natural stones – especially calcite-based stones such as marble, travertine, limestone, etc. – have a delicate chemical composition that may interact in “strange” (damaging) ways with the chemistry of cleaning solutions that were not specifically formulated for the task. Once you know WHAT to use, all you have to do is follow the basic DOs ‘n’ DON’Ts listed here:
GENERAL Spills can be very different in nature from one another. Many of them will turn out to be detrimental to stone if unattended. Orange juice, lemonade, wine, vinegar, liquors, tomato sauce, yogurt, salad dressing, perfume, after shave, wrong cleaning products and so on, through a long list, most likely won’t damage “granite” and “green marble” surfaces (at least in the short run), but will ETCH polished marble, travertine, limestone, onyx and alabaster. Therefore,
DO pick up any spill as quickly as you can get to it. DON’T rub the spill, only blot it.
DON’T use any generic cleaning product on your natural stone, or nearby it (i.e.: a liquid toilet bowl cleaner when the toilet is set on a marble floor), unless the label specifies that it’s safe on natural marble (cultured marble is manmade, and it’s basically a plastic material).
FLOORS
The means: A cleaning chore – any cleaning chore – is seldom a matter of a cleaning product only. Other factors are involved, such as a cleaning rag, a sheet of paper towel, a scrubbing pad, a squeegee, and so on. Without this additional means, the cleaner alone won’t do much good! What’s more, many a time the type and quality of the means is just as important as the quality of the cleaning product. If one uses some sub-par means, the cleaning product will not work at its best. This fact is never been truer than in the case of a glossy floor. I often noticed households using what I define as pathetic mops, many a time not so clean, either, teamed with tiny buckets on which to prepare the solution! A good-quality mop and the proper mopping bucket are keys to obtaining the best results at mopping your highly polished stone or porcelain floor. In all my experience I reached the conclusion that sponge mops are not the best types of mop for a highly polished floor. My very favorites are good sized, closed-loop cotton string mops. It’s always best to buy at least a couple of mop-heads, so that when one is dirty, all you have to do is throw it into the washing machine and use another one in the meantime. The mop bucket is very important too. Small buckets only hold little water (which, of course, will get dirty real quick), plus they don’t have any provisional means to wring the mop properly. Professional-type mop buckets with a wringer that hold a good 4 to 6 GL of cleaning solution are highly recommended. Excellent mop handles and heads, as well as a terrific bucket with wringer on wheels (by “Rubbermaid”) are available in the cleaning isle of The Home Depot and LOWE’S. They are relatively inexpensive, too. It’s a well worth investment if you have a lot of hard floors in your house!
The care:
NEWLY INSTALLED FLOORS. The best thing to have done to a brand-new polished stone floor is a detailing job by a properly trained janitor, or a professional stone refinisher. Detailing means deep-cleaning the floor virtually square inch by square inch, removing all possible grout residue or film and adhesive, taking care of possible small damages left behind by workers, or a possible few factory flaws, and open the pores of the stone by using some special cleaning agent, so that the stone can “breathe” and dry properly. Should you decide not to have your floor detailed,
DON’T damp-mop your floor immediately after installation and grouting. While you wouldn’t cause any real damage, the fine powder most likely left on the floor will be trapped in the water and may leave ugly and hard-to-remove streaks all over its surface. For the first week or so just vacuum and dust mop (NON-treated dust mop!) your floor as often as you can. You will know it’s ready to be washed when your hands remains clean (no whitish powder) after rubbing it on the floor. After that, or in the case of a
NEWLY RESTORED (REFINISHED) FLOOR.
DO damp-mop your floor regularly. Don’t use just water: it won’t cut through soil and will leave streaks. We recommend using a solution of water and “MB-1”, Marble, Granite and More Floor Cleaner, in the proportion indicated in the bottle’s back-label. DON’T use more than that. While no damage would occur, a visible film would be left on the floor surface that will require rinsing, thus wasting time and, what’s more, a very important feature of the product. DON’T rinse. The formulation of MB-1 includes specially selected inorganic salts that are meant to be left on the surface of the stone and act as moisturizers, as well as optical brighteners. When used in the right proportion and with the right means, MB-1 will leave your floor totally streak-free and it will actually enhance the shine of your floor! Should you decide not to use MB-1,
DON’T damp-mop your floor using a solution of water and stone soap. Like any other soap, stone soap WILL leave a hard-to-remove deposit on the surface of the stone. Stone soaps have very limited applications and, most importantly, quite different than cleaning a highly polished stone floor, no matter what the label on the bottle says (salesmanship has nothing to do with proper stone care!). Even so-called “rinse-free” stone soaps are a marketing scam. In fact, by reading the back label on their bottle, one will learn that every so often (when you can’t stand to look at your streaky and smeary floor any longer, that is!) you should be using a heavy duty stripper/degreaser (made by the same company, of course!) to remove all the “precious” scum that has been accumulating on your otherwise beautiful floor by not rinsing it after damp-mopping it. Always use a pH neutral floor detergent, opposed to a soap. (Even dish soap would create the same problem.)
DON’T damp-mop your floor using a solution of water with a commercially available cleaner, unless its label specifically indicates that its use is safe on natural marble (cultured marble is not marble: it’s manmade plastic material). Worse yet,
DON’T damp-mop your floor using a solution of water and vinegar. That would be literally devastating to the finish of marble, travertine, limestone, etc.! Vinegar is not a real cleaning agent to begin with, and it’s highly acidic (Acetic Acid). Use vinegar in your salad bowl, or for any other cooking purposes it was meant for!
If your floor is in a foyer, or any other room with direct access to the outside,
DO use proper floor mats. The leather or rubber of your shoes won’t damage your floor: dirt WILL. Don’t look for “pretty” mats, look for good ones! “ASTROTURF” mats by the Monsanto Co. (heavy-duty outside the door and finer inside) are among the best, in my professional opinion. They come in colors, too! A good Janitorial Supply Company should carry them and even custom cut them for you. Look in the Yellow Pages and call around. Most Janitorial Supply Companies do retail, and gladly so!
DO clean your floor mats often. When they get saturated with dirt and sand they won’t work anymore.
The preservation:
Many customers ask me what they should do to PRESERVE the factory finish (or the finish of a newly restored floor). No matter how elaborate the answer could be, at the end it only spells: W-O-R-K. No work = no shine. There is no exception to such a basic equation! If one’s willing to work in order to protect the “showroom finish” of his or her car by regularly waxing it, the same principle should apply to a polished stone floor (actually, even more so. After all, you don’t walk on your car!). “MB-7” Marble, Granite and More Polish Preserver is an excellent performer. Don’t expect miracles, though! For starters, the product should be applies as soon after installation (or restoration) as possible. It is meant to preserve the polish of the stone surface, not to make it! If you think to apply it when the floor is beginning to show damages (wear and tear patterns), MB-7 will do a terrific job at preserving … the damages! What’s more, by the same principle that a good-quality car wax will not preserve the original “showroom finish” of your car for ever, so will MB-7 with your polished stone floor. Absolute protection is impossible, but if used regularly as directed, MB-7 will make your floor age gracefully and it will never represent a real eyesore. MB-7 must be applied with either a professional, or a small residential floor buffer (available at Sears and other appliance stores).
KITCHEN COUNTER TOPS
I want to assume that your kitchen counter-top is made either out of “granite” or green marble or a hone-finished stone. (If you have polished marble or polished travertine, then there’s not much that can be done to maintain their highly glossy finish, other than … never use your countertop!). That said, there’s one thing and one thing only to keep into consideration. If a cleaning chemical was not specifically formulated to clean soil off while NOT interacting with the chemical makeup of the stone, it’s not safe to be used, period. This firm rule applies to all stone surfaces: floors, walls, etc. included, of course; but, for some mysterious reason, when it comes to countertops, there seems to be a particular widespread trend by which most stone dealers and fabricators recommend the wrong cleaning solutions to their customers. “Use a glass cleaner”, or “Use water with a little dish soap” are the most popular recommendations. They are wrong recommendations. So called glass cleaners may turn out to be too harsh to both the stone and the sealer (if one needed to be applied to it), while water and dish soap will leave an unsanitary film that will build up and become problematic to remove. (Try to wash your hands with dish soap and then rinse them under running water; observe how long and how much water it’ll take to rinse properly. To get the same result you’d have to rinse your countertop with a garden hose!) In conclusion, generic household cleaners off the shelves of the supermarket are out, and specialty cleaners specifically formulated to deal with the delicate chemistry of stone are, very definitely, in order. DO clean regularly you kitchen counter top only with products that specifically state to be safe on natural stone in their label. Our “MB-5” Marble, Granite and More Spray Cleaner, full strength, especially in proximity of the cooking and eating areas. Diluted in a proportion of 1:1 with water for less demanding situations (vanity tops, area of the countertop far from the cooking and eating one, etc.) is indeed an excellent performer.
DON’T let any spill sit too long on the surface of your counter top. Clean spills up (by blotting only) as soon as you can.
VERY IMPORTANT NOTICE: If because of some dried-on food or other matter particles your countertop needs some scrubbing,
DON’T use any green or brown scouring pad. The presence of silicon carbide grits in them WILL scratch even the toughest “granite”! You can safely use those sponges lined with a silvery net, or other plastic scouring pads. REMEMBER, it’s very important to spray the cleaner and let it sit for a while to moisten and soften the soil, before scrubbing. LET THE CHEMICAL DO THE WORK! It’ll make your job much easier and effective!
HOW ABOUT SOME EXTRA SHINE ON OUR POLISHED GRANITE? We have a product, MB-13, Polished Stone Dressing that does a terrific job at brightening up your polished stone surface! All its ingredients are classified as “food-grade”, therefore are 100% sanitary. If you use part of your countertop as a direct food-handling surface, however, we recommend not applying the product on those particular areas. While absolutely safe, it could give your food some undesired taste.
HOW ABOUT DISINFECTANT CLEANERS: We are very cautious at promoting and indiscriminately encourage the use of disinfectant/cleaning products to consumers. No matter what, if they have to meet their advertised performance, they are indeed products that must be handled with the utmost attention. If misused, in fact, they will do more evil than good. We do carry an excellent disinfectant cleaner, namely MB-15, Spray Cleaner Disinfectant, but we would like to make you aware of an important piece of information that, most likely, nobody else will ever disclose to you. All formulations of disinfectant cleaners, including the most popular household names, are strictly regulated by the EPA. There’s very little that the chemists of the various companies manufacturing such products can do to the formulas, which, basically, are all the same, though available in a few different versions. What this means is that when a company decides to carry one such product, it can only choose between the existing formulations allowed by the EPA, and strictly adhere to them. The penalties for changing, even if so slightly, any one of the components, and/or their dosage, are quite severe and could include imprisonment. The label of the product is also strictly regulated by the EPA (actually written by it), and is mandated by the formula that was chosen among those available. Some of the features of the product can be deleted by the official EPA label, i.e.: most formulations available – ours included – do kill the HIV virus, among many others; but we chose to keep that particular feature off the label of our own bottle since we don’t plan to sell to hospitals or other institutions that may have to deal with such a particular virus; just the specific directions on the use of the product for that one particular task would have filled half the space available for the back label! Other than that, not a single word can be changed or added. While we do appreciate and wholeheartedly endorse such strict regulation, sometimes – we have to admit it – things can get a little bit … on the humorous side! Let’s not forget, in fact, that we’re dealing with bureaucrats, no matter how well intentioned and (allegedly) well informed. There is only one formulation available that allows in its label the words “Tile and Stone”. By further reading the label, one finds also a reference to “sealed marble”. If a manufacturer chooses a formulation different from that one, is not allowed to use such wording. Now the funny part: we did extensively test – like we always do – such particular formulation on a vast array of natural stones (somehow, we do not trust much the “stone expertise” of bureaucrats! And that “sealed marble” definition …) and found out that it was not safe on a few popular marbles, even if sealed with an impregnator sealer for stone! It was etching them! Further investigation, brought into the open that what seems to be the EPA’s definition of “sealed marble” makes reference to marble coated with a shellac-type topical “cocoon”, which is still quite popular in the furniture industry (many marble table tops and chest-drawer tops are still treated like that). So basically, that particular product can be safely used on shellac, not marble! But what about your marble vanity top, or your foyer floor? They don’t have that stuff applied on them, do they?! So, we discarded that particular formula and chose a different one that turned out to be the only one totally safe on all stones we tested it on (a whole lot, believe us!). But guess what: like we mentioned before, we are not allowed to mention anything about stone on our label, because the EPA label of that particular formulation does not include that!! A less scrupulous competitor of ours preferred to choose the unsafe product over the safe one, because it will allow them to use the words tile and stone on their label, thus greatly helping their marketing department. Something bad happens to your marble? They’re off the hook: “Hey, take it up with the EPA, we didn’t formulate the product and wrote the label, they did!” We at MB Stone Restoration &n Supply don’t care much about these marketing trickeries. We care more about your stone than a bunch of words, which could only help us sell more. We hope you will appreciate that.
That said, of course we’d like you to buy our product (that’s what we are in business for, after all!), but we want to make as sure as possible that you won’t misuse or overuse it. “Education before any sale!” is our corporate motto. It is not just a slogan. We do mean it.
VANITY TOPS DO clean it regularly by using a spray stone cleaner. Should you want to use our “MB-5” Marble, Granite and More Spray Cleaner, considering the typical light-duty cleaning necessary on a vanity top, you can dilute the product in a proportion of 1: 1 with tap water and still perform flawlessly (you can buy an extra spray-bottle at any hardware store). As far as the mirror over your vanity top is concerned, DON’T take chances with a regular glass cleaner: possible over-spray could spill on the marble surface and may damage it. Therefore,
DO clean your mirror with the same solution of water and MB-5; even if you over-spray it, nothing bad is going to happen to your marble.
DON’T use any powder cleanser, or – worse yet – any cream cleanser, such as “Soft Scrub”.
DON’T do your nails on your marble vanity top, or your perm nearby it.
DON’T put any wet bottle onto it (perfume, after-shave, etc.). Keep your cosmetic and fragrances in one of those pretty mirror trays, and make sure that the legs of the tray have felts tips.
If you want to add some extra shine to your polished stone countertop surface and help prevent soiling,
DO use our MB-13, Polished Stone Dressing. Follow the directions on the bottle, and get ready to be amazed by the results!
SHOWER STALLS
Tiled shower stalls – whether ceramic or natural stone – represent a very delicate and demanding environment, because of the heavy-duty nature of their use. There is quite a difference in use between the walls of the bathroom outside the stall, and the same walls inside it! Because of that, the first real and utmost concern is that the installation is done properly, because a poor executed installation will inevitably lead to an expensive failure. Besides all the plumbing work (which also includes the shower pan) and the proper sheeting with the right material (no green-boards there!), it is important that a provision of 1/16” gap (the thickness of a round toothpick) in between tiles is made to grant for proper grouting. While in the walls outside the shower stall an installation “butt-jointed” (that is without any gap in between tiles) is acceptable and, I concede it, prettier too, the same type of installation inside the stall will mean a virtually sure installation failure. In fact, the grout would only bridge the bevel where the tiles meet, but won’t have any “root”. As a consequence, with the hot water hitting those grout lines day in and day out, plus the heavy-duty cleaning that’s typically necessary inside a shower enclosure, that “ornamental” grout will first soften, and then come out. The consequence of that is that the water will start finding its way in between tiles, behind them, and, by gravity, accumulate under the tiles of the shower floor creating all sorts of problems that, eventually, will call for a total remaking of the shower stall.
Assuming that your shower stall was installed properly (every so often, DO monitor your grout and caulk lines, and address any problem immediately!),
DON’T use any cleanser, either in a powdery or creamy form.
DON’T use any generic soap film remover, such as ‘TILEX SOAP SCUM”, or “X-14 SOAP SCUM”, or the likes on your polished stone shower stall.
DON’T use any generic mildew stain remover, such as “TILEX MILDEW STAIN REMOVER”, or ‘X-14 MILDEW STAIN REMOVER” or the likes on your polished stone shower stall.
DON’T use any magic self-cleaner, such as “SCRUB-FREE” and the likes, or any harsh disinfectant, such as “LYSOL”.
DO clean your shower stall daily. The easiest way is to use one of those windshield-cleaning tools (the one with a scrubbing net on one side and a squeegee blade on the other side). After everybody has taken a shower, spray the walls and floor of the stall with a diluted solution of water and MB-5, scrub swiftly, then squeegee. When eventually you will notice an accumulation of soap film (especially on the lower part of the walls and on the floor pan) that looks and feel like wax (it will leave a whitish residue on your fingertips when you rub then on the stone surface), use “MB-3” Soap Film Remover to clean it off. MB-3 was specifically formulated to be effective at doing the job of cleaning soap scum and hard mineral deposits, while not interacting with the chemistry of natural stone.
If, over time, some mildew will appear on the grout lines of your shower enclosure,
DO clean the mildew stain with “MB-9” Mildew Stain Remover. This product, too, has been formulated to be safe on natural stone, while very effective at removing mildew and other biological stains.
COMMODES
If your toilet bowl sits on a marble or other natural stone floor,
DON’T use any generic toilet bowl cleaners: possible spills will dig holes in your marble! Clean your bowl with a powdery cleanser and, if some extra disinfection is desired, after cleaning you can spray your commode liberally with our excellent MB-15 cleaner/disinfectant. Possible spills will NOT damage natural stone!
TO SEAL OR NOT TO SEAL? “Marble and travertine are very porous … you must seal them!!” And: “All granites must be sealed!!”
You’ve probably heard sentences like that from every single soul that’s been involved in your “stone adventure”. Are all these stone “gurus” right? How did they get their experience and stone education?
The answer to the first question is a big NO. They are not right. In fact, they are totally wrong!
The answer to the second question is: from various salesmen and importer/distributors’ invoices!
Let’s face it, natural stone is not simple. If one sells natural stone without having the slightest real education about it, that one will have to face problems coming in the form of complaints from his or her customers. Since it seems that nobody is interested at getting even a basic education about stone, it becomes natural, as an alternative, to gladly embrace any blanket rule that comes along, promoted in the form of some sort of a “miracle-in-a-bottle” by a whole army of salesmen who, of course, never even looked at the cover of a petrography book!
Blanket rules are an oxymoron when applied to a complex and so diverse material like natural stone. The exceptions are so many that the rules would lose any meaning. And, in fact, they do!
Let’s do a tiny bit of homework. “Marble and travertine are very porous … you must seal them!!” WRONG! Marble (especially all those mercantile marbles that are actually compact limestone) and travertine are NOT very porous. If you don’t believe me, try to spill a few drops of water, say, on a polished travertine tile, and observe how long it will take to be absorbed (the area under the water would become darker). A long, long, loooong time! So, what’s the story with all those stains on polished marble and travertine? Very simply, they are not stain. They are, in fact, marks of corrosion (etch marks) that any acidic substance will leave behind when becoming in contact with the surface of the stone. They do look like water stains, or water rings, but they’re neither stains, nor were they generated by water. The deriving (surface) damage has no relation whatsoever with the porosity of the stone (which determines its absorbency), but it’s exclusively related to its chemical makeup. No sealer in the entire world could do anything to prevent such kinds of damage.
“All granites must be sealed!!” TRUE. Granite is indeed more porous than marble and will stains if not protected with a good-quality impregnator-type stone sealer. So then, the salesmen are right after all! What’s the problem?! Well, only a small one: The vast majority of the stone traded as granite are, in fact, related to granite like a cat to a cow! Consequently, while it’s true that real granites need to be sealed, there are many other “granites” – much denser than granite – that need no sealing. Some will even develop problems related to the sealer, if sealed nonetheless! At the other end of the spectrum, some other “granites” are so darn porous, that no sealer will do a satisfactory job at sealing them 100% and for a long time! Again, keep in mind that I’m NOT talking about a few samples, here: I’m talking about the vast majority of the stones traded as granite! So, how good is the blanket rule to seal everything in sight that doesn’t move?
I did study (some) petrography and chemistry applied to minerals, and all my research led me to one very sound conclusion: The more you leave the stone alone, the better! Let’s make no mistake, sealers are a good invention, and do help a great deal when used in the right applications, but the way they are promoted and touted makes them one of the most overrated, oversold and over applied product in the history of mankind!
Sealers for stones, which are below surface, penetrating-type sealers (better referred to as “impregnators”), were designed to do one thing and one thing only: clog the pores of the stone so that alien liquids will not be absorbed by it. But this is only one factor of our “stone equation”! The other factor being the environment where the stone is going to be installed. To determine this second and just as important factor ask to yourself: “What kind of chances there are that some coffee or cooking oil will be spilled on my stone – and without realizing it (so that it’s going to sit on it a long time) – to call for a sealing job?” The answer to that question will tell you exactly how much you actually need to have your stone sealed, assuming that’s a stone that will take in a sealer to begin with. If you conclude that the chances are minimal, then for the sake of your stone, leave it alone! It makes no sense to seal, say, a Botticino Classsico, or a Travertine foyer or shower-stall: those two stone are not very absorbent to begin with, and the chances of staining (in a foyer, or inside a shower enclosure) are remote to say the least. As it makes no sense to seal, say, a larvikite, or anorthosite kitchen countertop (both stones are traded as granite): the sealer itself has no chances to be absorbed due to the density of the stone. Many a times, I witnessed “weird” problems in the form of etching occurring on “granite” countertops. It turned out that the little residue of sealer left on the surface of the stone (nothing went inside it!) was actually etching, not certainly the stone! Once I professionally removed the sealer, everything was fine! Again, what sense would it make to seal walls cladded with White Sardinia? The stone – a true granite – does need sealing if you use it as a kitchen countertop, because of the likelihood of staining agents being spilled onto it, but what king of chances are there to spill some staining agent on a wall?!
Bottom line, no “miracle-in-a-bottle” promoted by the best salesmen can even vaguely be intended as a substitute to professionalism! Like I said before, sealers do help a great deal, but one must learn where and when to apply them.
I devised a little, easy test, to find out if your stone is the proper one for the application to begin with, and if it needs sealing or not. You can find my “lemon juice test” by reading our other piece of literature titled, “How to Shop for a Granite Kitchen Countertop”.
If, because of the type of stone, and of where it was installed you conclude that it needs to be sealed, then I recommend using “MB-4” Impregnator for Stone and More. It’s very effective and comes with a 5-year warranty.
ABOUT “WATER STAINS” OR “RINGS”
Polished marble, travertine, onyx, limestone, etc. are all calcite-based stones and, as such, are affected by pH active liquids, mostly acidic in nature. In layman language, when some acidic liquid hits a polished marble, travertine, etc. surface, it etches it. That is, it leaves a mark of corrosion that looks like a water-stain or ring, or whatever shape. Such surface damage has nothing to do with the absorbency rate of the stone (typically quite low, anyway), but exclusively with its chemical makeup, which, as mentioned before, is mostly calcite (Calcium Carbonate, CaCo3). Trying to remove the “stain” by poulticing it would be useless exercise, since it is not a stain, no matter what it looks like. You’re in fact before a small, yet full-fledged restoration project: The damaged surface must be re-polished. To do that, you can’t use some sort or “marble polish” (wax that is). It won’t work, because marble is polished by abrasion and friction, like gemstone, not by buffing it up! Our MB-11, Polishing Powder for Marble is a professional-grade product (yet user-friendly) that will actually re-polish the damaged area of your stone and bring it back to its original factory finish! Some etch marks may turn out to be too severe to be handled by a polishing powder (the stone must be honed first), but our statistics indicate that a good 75% of all etch-marks found in residential dwelling are successfully repaired with our MB-11.
HOW ABOUT IF WE GET A REAL STAIN?
We have a specific piece of literature on stain removal that’s available in our “Educational Literature” section. www.mbstone.com. It’s less expensive than some “professional stain removal kit” that no true professional ever uses!
As a final consideration from a stone lover like myself, I would like to submit to your attention that it took Mother Nature up to a few hundreds of thousands of years to make the stone that you now proudly own and embellishes your surroundings. Think about it, each and every piece of stone you own has no match in the entire world! You must appreciate and respect that. Along with its unmatchable beauty, however, you have also to accept its physical limitations. Don’t consider and treat your stone like just another commodity. You have to feel responsible for its proper maintenance and care, because you did not just buy your stone. You actually adopted it.
© Maurizio Bertoli II/89-I/03
DO contact us through our web site: www.mbstone.com/ “Contact us” section, if you need additional assistance.
Optionally, you can order by phone calling us toll free at: 1(888) 473-3235.
MANKIND SHOULD MASTER NATURE BY UNDERSTANDING, NOT BY FORCE
