Argthtjtr

I was fascinated by his humanist / humanistic view.

Which one is the correct or more idiomatic option?

I have seen both being used online in phrases such as "humanist(ic) view" and "humanist(ic) approach".

With words that end in -ist (often they have a -ism form, but not always), many times the -ist word is a person, and the -istic form is an adjective describing either the person or their philosophy, belief, behavior etc.

For example:

• tourism (the thing)
  
  


• tourist (the person)
  
  


• touristic (having to do with tourism)
  
  
  


• materialism (the thing, either preoccupation or philosophy)
  
  


• materialist (the person)
  
  


• materialistic (to describe a materialist or having to do with materialism)
  
  
  


• opportunism (the thing, the method or behaviour)
  
  


• opportunist (a person who uses opportunism)
  
  


• opportunistic (to describe an opportunist or having to do do with opportunism)
  
  

Although this is a common pattern, the -ist and -istic forms are both often accepted as either adjectives or the -ist form is accepted as an attributive modifier (noun adjunct/attributive noun). It seems that what makes one form acceptable with regard to certain words is simply established by convention. Look at this Google NGram for results for:

individualist philosophy

individualistic philosophy

collectivist philosophy

collectivistic philosophy

It shows that in this case individualistic is more frequent than individualist, but collectivist is more frequent than collectivistic. Some dictionaries don't even list "collectivistic" as an inflected form. However, even though this site's spell-checker doesn't recognize "collectivistic", it doesn't mean it's not a word. Many dictionaries recognize it. These differences are probably historical accidents.

Given that some dictionaries recognize the -ist form of the word as an adjective and some don't, in many cases it's not exactly clear whether you're looking at an adjective use or attribute noun use. Random House Kernerman Webster's College Dictionary only lists capitalist as a noun. However American Heritage Dictionary lists it also as an adjective, and defines it as:

"adj. capitalistic."

I hear terms like "misogynist comments", and although I'd tend to use "misogynistic", many people do this, and plenty of dictionaries give their approval of "misogynist" being an adjective.

In other cases there's a more consistent separation between the -ism, -ist and -istic, such as sadism, sadist and sadistic, where you'll rarely hear people say a "sadist person" or "sadist tendencies", as the word "sadistic" is now overwhelmingly established as standard as the adjective.

So long story short, the -ist/-istic difference for noun/adjective is present in many words, but the word ending with -ist is often used as an adjective or as an attributive noun.

humanist or humanistic

Which one is the correct or more idiomatic option?

As I mentioned above, each word is different as to which suffix is used. Here are the NGram results for "humanist/humanistic views". They're neck and neck, so take your pick.

You COULD argue, if asked what the difference is, that "humanist" describes things more having to do with a humanist person whereas "humanistic" describes things having to do with humanism, but I really don't think this is the case.

To a first approximation they mean the same thing. However, "Humanism" is a socio-political philosophy, and someone who adheres to that philosophy is considered a "humanist", so that word might be used to refer to such a person or his philosophy, while "humanistic" is a more general term use to refer to less dogmatic concepts or tendencies.