Philosophy and Proofs
Atheism includes any philosophy which claims that no God or gods exist, including any rational or reasoning creator of the universe.
Christianity is the philosophy that claims that Jesus of Nazareth is the Son of God and Jewish Messiah (or Christ); that he was crucified, died and was buried, and rose again three days later; that his death was an atoning sacrifice for the sins of his followers; and that placing one's trust in Jesus is how any sinful person can be forgiven and made righteous before their creator.
Deism refers to any philosophy which claims that there is a supreme creator of the universe who has no ongoing involvement with what is created apart from the initial act of creation itself.
Empiricism describes any philosophy which claims that all knowledge originates in experience, denying the validity of both deductive reasoning and divine revelation.
Islam refers to the specific philosophy of the Muslims, a monotheistic and unitarian belief system declared by Muhammad in 610 AD and described in the book known as the Qur'an.
Monotheism refers to any philosophy which claims that there is only one supreme creator of the universe.
Open theism refers to any philosophy which claims that there is a supreme creator of the universe who does not foreknow the outcome of human choices.
Polytheism refers to any philosophy which claims that there are multiple supreme creators of the universe.
Rationalism describes any philosophy that claims that beliefs and opinions should always be logical, deductive conclusions rather than being based on experience, observations, religious teachings, or divine revelation.
Theism includes any philosophy which claims that some kind of God or gods exist.
Trinitarianism is the philosophy that there is only one God in terms of essence or being; and that the one God is revealed through three eternally distinct persons, specifically, the Father, the Son (Jesus of Nazareth), and the Holy Spirit. Trinitarianism is unique to Christianity.
Unitarianism refers to any philosophy which claims that divine sovereignty is not shared in any way.
In Printed Form
Along with numerous other authors including Don Landis, Bodie Hodge and Roger Patterson, Timothy McCabe contributes analyses of various world religions and cults in this volume from Master Books.
"Can non-Christian views be internally consistent?"
Non-Christian worldviews cannot be internally consistent. While the above statement is true, proving it is a different matter. However, its truth follows from the basics of the Christian faith. Since, in Christian theology, the Christian God is understood to be necessary, any deviation from that which is necessary would be impossible, entailing a logical contradiction.
"How do we know that God(s) still exists today? "
God created time (Genesis 1:1; 2 Corinthians 4:18; 2 Timothy 1:9; Titus 1:2; Hebrews 11:3; Jude 1:25). As the One Who created time, He is inherently atemporal (or omnitemporal depending upon which aspect of His eternality we are emphasizing) (Deuteronomy 33:27; 1 Timothy 1:17; Hebrews 9:14). Given this, He is definitively always the same (Exodus 3:14; Malachi 3:6; James 1:17). If He is always the same, He cannot cease to exist.
"What do Mormons believe? Do you consider them Christians?"
This depends on the definition of Christian. It also depends on your definition of Mormon. For "Mormon", I will take this word to mean a member of the Church of Jesus Christ of Latter Day Saints (LDS), the largest and most missionary-oriented Mormon denomination in the world. If by "Christian" we mean someone who calls them self a Christian, then Mormons are definitely Christians, as they do consider themselves to be.
"Why did God only send Jesus to Palestine at one particular point in history? If God wants everybody to be saved, wouldn’t the gospel have spread a lot faster if he had sent Jesus to every place on earth in all time periods?"
Are you sure that God wants everyone to be saved? There are many Christian philosophers who do indeed claim that this is the case, but it seems to me that this concept contradicts scripture. John 12:39-40 (re Isaiah 6:8-10) For this reason they could not believe, for Isaiah said again, "HE HAS BLINDED THEIR EYES AND HE HARDENED THEIR HEART, SO THAT THEY WOULD NOT SEE WITH THEIR EYES AND PERCEIVE WITH THEIR HEART, AND BE CONVERTED AND I HEAL THEM.