Science has a way of making a man feel confident. It gives him a sense of being in control of the universe. Man feels powerful as a result of the assurance he receives from scientific research. It is partly emotional, and largely intellectual. It is a potent combination of knowledge and a "buzz." The buzz corresponds to how highly a person views science in the grand scheme of things.
The term "scientism" refers to the belief that science tells us everything there is to know concerning truth and reality. Only scientific claims are thought to be meaningful. And it's quite easy to see how this belief system can lead its adherents to be dismissive of any other truth claims.
Sadly, some scientists elevate their scientific knowledge to the point of spiritual adoration and praise. For these folks, science becomes the "anti-God." They attempt to use it as a viable defense against the Christian God. All of that supernatural stuff is thought to be nothing but mystical mumbo jumbo.