Induction
From The Oxford English Dictionary (OED); to induce (in relation to science and logic) means “to derive by reasoning, to lead to something as a conclusion, or inference, to suggest or imply,” and induction “as the process of inferring a general law or principle from observation of particular instances.”
Science is all about predicting the outcome of future events and predictions based on past experiences. Every time a bridge is built, it is built using techniques that have worked in the past.
The problem here is, there really is no way to tell just because something happened many times in the past does not mean it MUST happen in the future. Yet scientists say that they “KNOW” something, they have PROVEN something and they will get same results in the future.
How they can be so sure? The answer is that science is based upon INDUCTIVE reasoning.
This way of thinking is indeed a paradox. It is impossible to predict the future and there is no justification for reasoning that outcomes of past events predict the future. Yet science is precisely based upon this idea.
David Hume was one of the many thinkers who had troubles with this idea. What Hume believed was that induction was illogical and irrational.
He asserted that no amount of observed instances can possibly predict the future. He called the knowledge from the past observation as “expectational knowledge”.