Can one make up his own mind about Scientology?

One can and indeed one should. Scientology enables a person to think for themselves. There is no purpose served in practicing or studying Scientology because someone else wants one to. But if a person has taken a good look at life and decided they want to make things better, the best thing is to start and find out for oneself what Scientology can do. One should read one of the beginning books by L. Ron Hubbard.