Science teaches that human life begins...

"Science teaches that human life begins at conception. If it is also true that it is affirmed by religion, it does not for that reason cease to be a strictly scientific truth, to be transformed into a religious opinion. He who denies that human life begins with conception does not need to contend with religion, but science. To deny this certainty of biology is not to express a lack of faith, but a lack of basic knowledge of human genetics, something that is even known by the general public."
~ Ecuadorian Federation of Societies of Gynecology and Obstetrics, April 17, 2008 ~

To concur with the intention...

"To concur with the intention of another person to commit suicide and to help in carrying it out through so-called "assisted suicide" means to cooperate in, and at times to be the actual perpetrator of, an injustice which can never be excused, even if it is requested. In a remarkably relevant passage Saint Augustine writes that "it is never licit to kill another: even if he should wish it, indeed if he request it because, hanging between life and death, he begs for help in freeing the soul struggling against the bonds of the body and longing to be released; nor is it licit even when a sick person is no longer able to live".
~ Pope John Paul II, The Gospel of Life, no. 66 ~

It is not sufficient...

"It is not sufficient to think that, since candidate X takes the 'right position' on other issues such as the economy, foreign relations, defense, etc. but only goes wrong on abortion, one can in good conscience, vote for him/her. Abortion deals with the first and most basic human right, without which there is nothing left to talk about."
~ Father Matthew Habiger, OSB, HLI Reports, April 1996 ~