In 1830, at the age of 23, Parley Pratt, who would soon become a member of the original Quorum of Twelve Apostles and one of the great missionaries and writers of early Mormonism, encountered the Book of Mormon for the first time.

"I opened it with eagerness," he later recalled in his "Autobiography," "and read its title page. I then read the testimony of several witnesses in relation to the manner of its being found and translated. After this I commenced its contents by course. I read all day; eating was a burden, I had no desire for food; sleep was a burden when the night came, for I preferred reading to sleep.

"As I read, the spirit of the Lord was upon me, and I knew and comprehended that the book was true, as plainly and manifestly as a man comprehends and knows that he exists. My joy was now full."

Determined to meet the Prophet Joseph Smith, he traveled to Palmyra, where instead he found Joseph's brother Hyrum, who told him about the founding events of the Restoration. On Sept. 1, 1830, Oliver Cowdery baptized him. Less than three weeks later, he taught and baptized his own younger brother, Orson.

His description of how he came to a conviction of the truth of the Book of Mormon is intriguing. He mentions no audible voice of God, no angelic visitation, no vision of ancient Zarahemla. Nor does he describe a lengthy process of study and research, amassing books about ancient America, meticulously comparing biblical passages to the Nephite text.

He just knew.

This is precisely how most of us make many, if not all, of our most fundamental, life-forming decisions. We don't consider evidence and analysis on the topic before concluding that we exist. We know it directly. We don't typically choose a spouse, launch a career, make a life-long friend or accept a job offer on the basis of notebooks full of data marshaled into arguments and counter arguments and then weighed according to a probability calculus.

Nor, for that matter, do we typically wait for an angelic command or a divine appearance.

We go, all things considered, with what feels right.

We move forward on the basis of a very personal combination of evidence, reason, feelings, hunches, hopes, even "tastes" — and yes, Latter-day Saints believe, often under the influence of the Holy Ghost — that can't be reduced to a set of logical propositions or a computer algorithm.

"And Jesus, walking by the sea of Galilee, saw two brethren, Simon called Peter, and Andrew his brother, casting a net into the sea: for they were fishers.

"And he saith unto them, Follow me, and I will make you fishers of men. And they straightway left their nets, and followed him." (Matthew 4:18-20)

"Straightway." Not after a year-long investigation. Not at the end of a rigorous program of study and research.

They just knew.

Living in a world where we know the facts only "in part," and "see through a glass, darkly," under conditions of incomplete information, we have little choice but to make fundamental decisions based, in the end, upon what "feels right" to us. (See 1 Corinthians 13: 9, 12.)

But this is the way it's supposed to be. We're in this life, at least partially, to learn to "walk by faith, and not by sight" (2 Corinthians 5:7).

Our assurance is that, as we step forward in faith, God will be there and our trust in him will prove justified and be rewarded. "It is by grace that we are saved, after all we can do" (2 Nephi 25:23).

"This is good doctrine," said the Prophet Joseph Smith in his famous 1844 "King Follett Sermon." "It tastes good. I can taste the principles of eternal life, and so can you. They are given to me by the revelations of Jesus Christ; and I know that when I tell you these words of eternal life as they are given to me, you taste them, and I know that you believe them. You say honey is sweet, and so do I. I can also taste the spirit of eternal life. I know that it is good; and when I tell you of these things which were given me by inspiration of the Holy Spirit, you are bound to receive them as sweet, and rejoice more and more."

Daniel C. Peterson is a professor of Islamic studies and Arabic at BYU, where he also serves as editor in chief of the Middle Eastern Texts Initiative and as director of advancement for the A. Maxwell Institute for Religious Scholarship. He is the founder of MormonScholarsTestify.org. He blogs daily at dcpsicetnon.blogspot.com.