Henry M. Morris, whose writings describing what he saw as a divinely created world helped ignite a fierce national dispute about creationism and evolution, died Feb. 25 at a convalescent hospital in Santee, Calif., near San Diego. He was 87 and had a series of strokes in recent weeks.

Mr. Morris, who coined the term "creation science," founded the California-based Institute for Creation Research in 1970 and built it into an organization of far-reaching influence as the intellectual center of the creationist movement.

He wrote more than 60 books, most of which took aim at evolutionary theory and offered justifications for creationism, which asserts that a divine being created Earth and all living beings in their present form. He based his writings on his belief that the Bible is true, down to the smallest detail.

Mr. Morris, whose scientific training was as a hydraulic engineer, applied his knowledge of water movement to the biblical account of Noah's flood. His 1961 book, "The Genesis Flood," written with John C. Whitcomb, was the first significant attempt in the 20th century to offer a systematic scientific explanation for creationism and remains in print. Even a longtime opponent, the late Stephen Jay Gould, acknowledged it as "the founding document of the creationist movement."

Supporters and foes alike regarded Mr. Morris as the "father of modern creation science" or sometimes, more waggishly, as the "Darwin of the creationist movement."

"He had an enormous influence," Edward Larson, author of "Evolution: The Remarkable History of a Scientific Theory," said. "He literally set the terms of the debate for the second half of the 20th century."

Mr. Morris' ideas have been roundly rejected by mainstream scientists but continue to hold considerable sway over the beliefs of millions of Americans and others around the globe. His books became the intellectual bulwark of a movement led mostly by fundamentalist Christians who seek to expose what they see as flaws in the theory of evolution. The books have been the basis for many attempts to introduce creationism or similar theories in public schools.

Mr. Morris was a staunch "young Earth" creationist who believed the Earth was less than 10,000 years old and was made in six 24-hour days, with mammals and human beings created on the sixth day. He maintained that fossils were animals that died during the biblical flood or were placed in rocks to give the appearance of age.

"If the Bible is the Word of God — and it is," he wrote in his 1974 book, "Scientific Creationism," "then it must be firmly believed that the world and all things in it were created in six natural days and that the long geological ages of evolutionary history never really took place at all."

In 1987, the Supreme Court ruled that creationism was a form of religion, not science, and could not be taught in public schools. Mr. Morris and his team at the Institute for Creation Research then rewrote some of their textbooks, excising references to Scripture to convey a stronger sense of rational scientific inquiry.

In his frequent public appearances, Mr. Morris maintained a cordial, grandfatherly mien, even toward his antagonists, but he rarely testified in the court cases his writings prompted.

"He was a real gentleman," said Larson, who received the 1998 Pulitzer Prize for his book "Summer for the Gods: The Scopes Trial and America's Continuing Debate Over Science and Religion."

"He could stand up for his positions ably in a debate. He was confident in the correctness of his position."

Mr. Morris' views rested on what he saw as a simple, fundamental truth: "The final and conclusive evidence against evolution is the fact that the Bible denies it."