Some of my friends get this argument all the time from their less mathematical business-manager bosses. "Sure, probability applies to playing cards, they're random, but it doesn't apply to business_process_X, because there things happen for reasons!" (I've even heard "sure, probability applies to baseball players, but it doesn't apply to website visitors"!)

Pretty much everything that we use probability to model has underlying causes and reasons, if we could only detect and measure them (at least until you get down to quantum mechanics), but probability can still be a useful way to model problems where either we don't fully understand the underlying causes, or the underlying causes are just too complicated and tangled to directly model.

Did you bother to read the articles?

There are over 200 different types of cancer. Not all of these are caused by contact with carcinogens. So, for these cancers it's pretty much "luck" whether you get them or not. Not smoking; sensible drinking; etc will not prevet you from getting them.

Please provide evidence when you say these kinds of things. Causation is rarely as intuitive as you would like to believe.

I think that's a bit unfair. Sure, we can play semantics and claim it's technically incorrect to say "smoking causes cancer" because if it did everyone who smokes would get cancer, and that isn't the case.

However, we are aware of quite a few known, and many probable, carcinogens.[1][2] Among women, breast cancer comprises 60% of alcohol-attributable cancers.[3] And to support the claim that certain foods, when prepared in certain ways, can become carcinogenic take a look at the research on Heterocyclic amines,[4] and acrylamide.[5]

1. http://www.cancer.org/cancer/cancercauses/othercarcinogens/g...

2. http://en.wikipedia.org/wiki/List_of_IARC_Group_1_carcinogen...

3. http://onlinelibrary.wiley.com/doi/10.1002/ijc.21903/abstrac...

4. http://en.wikipedia.org/wiki/Heterocyclic_amine#Heterocyclic...

5. http://en.wikipedia.org/wiki/Acrylamide#Toxicity_and_carcino...

Waiting for a strong causal link, especially when there is a high level of statistical relationships, can mean we might be waiting too long to take serious action.

If repeated studies show strong associations, like say between cigarettes and cancer, it would make sense to take some steps to prevent the potential cause.

Well, carcinogen is one those things that has been known for decades causing cancer. And yes, human-being can make the difference whether they have those unnatural carcinogens or not.

There are plenty of "natural" carcinogens too. Avoiding carcinogens may reduce your cancer risk, restricting yourself to things that are "natural" won't.