Does IQ determine your success?

Yes, and also no.

Firstly, if you were to take a "real" IQ test, then that result is a strong statistical predictor of multiple future life outcomes, whether if it is income, education level, health, even longevity. There are multiple of studies that confirm these correlations of predictions. So in that sense, IQ "predicts" your future "success".

However, do not think of IQ as Intelligence, it is still debated that what IQ actually measures. Its also difficult to elaborate on what we mean by intelligence. Think of the "IQ Score" as simply an abstract number that is statistically correlated with a group of other abstract numbers (one such as future annual income). And be aware of any philosophical, political, personal, conclusions you might jump to from the "yes" answer before.

Pretty much none of the "IQ tests" that you have heard of or encountered have any much validity. Online tests, apps, popular "Test Your IQ" books, etc, there are invariably not properly designed, in other words they are complete BS and taking them for fun with your friends is fine but don't take those tests seriously. To get a real IQ number, you need to take a test managed by a professional, and licensed to that professional by one of the big test publishing companies, tests such as Wechsler or Stanford-Binet. Do keep in mind that there is also that different tests are used for children, adolescents, and adults, in other words people of different age groups require different tests to test their capability at that age. Most online tests and their sort are more or less scams to generate web traffic for profit, so please do not put much trust in them.

An IQ score compliments success, and is also a poor "measure of the man". More in the abstract sense in what we know about IQ correlations concerns to groups of people. These are still statistical measures. Their relevance for an individual is difficult to evaluate perfectly at best. In other words, for a large group of people, IQ is one of the strongest predictors of future "success" that we know of, but for an individual person, it is a weak indication. For instance, in one major study correlating IQ and SES (social economic status of parents) with future income, IQ had as much as three times higher "beta" than SES. That basically means how "smart" you are is much more crucial here than who your parents are. However, the total amount of R-squared of using both variables was only 0.14. That means, knowing your parents SES as well as the child's IQ, together only explained approximately about 14% of your future outcome. From the perspective of the decisions available to that child, that's not a very big number at all. IQ does predict your success but it is also essential to keep in mind that so what if it does? And it is not the only factor to determine your success, one of which is the adversity quotent(AQ) which is the ability to turn obstacles into opportunities, it measures the ability of whether someone is able to deal with the adversities of their lifes. Often times, people say that they are not smart or have "low IQ" and feel demoralized about it, we have to be more open-minded than that, be aware that high IQ increases the odds that you will be "successful", but does not guarantee success., intelligence compliments success but it does not mean that you will be successful just because you are intelligent.

Secondly, IQ is a very strong predictor of academic succeess, but a poor predictor of socioeconomic success. So it is definitely entirely possible that you will get great grades but then have a mediocre career.

The claim from socrates is that only in striving to come to know ourselves and to understand ourselves do our lives have any meaning or value.