Tom Riddle, however started the Dark Arts from a young age. He killed his Muggle father and grandparents. But, think now. If your mother was a witch, terrorized, and desperate for love, and after a love potion wears off, your father leaves her to die of heartbreak, would you not be angry? Would you not want to pay him back for what he did?

Tom Riddle killed his Muggle father and grandparents for a reason. But as it goes, the first time you use the Dark Arts, or an Unforgivable Curse, you can either try harder and harder to withdraw, with a good result, the right thing, or you can effortlessly continue along the Dark path and meet your demise, the wrong thing.

Tom Riddle had been through a lot, and his Muggle hating intincts took over, saying, all Muggles are like your father, put an end to them. He continued through the Dark path, and he felt an urge, unresistable when you are so far up the Dark path, to rise to power, rule the Muggles, rule the world! And other witches and wizards joined him, a little less far than Voldemort, feeling that same urge.